Contact field for plug-in connectors

RELATED APPLICATION

p-0002This application claims priority to German Application No. 102010014294.8, filed on Apr. 8, 2010, the disclosure of which is incorporated herein by reference.

FIELD OF THE INVENTION

p-0003The invention relates to a contact field for plug-in connectors

SUMMARY OF THE INVENTION

p-0004In network technology, there arises a problem with near-end crosstalk and with reflections at plug-in connectors particularly in the case of increasing transmission speeds.

p-0005In particular in the case of the popular twisted-pair cabling which is schematically shown in <figref idrefs="DRAWINGS">FIG. 1</figref>, there arises a problem with near-end crosstalk between certain pairs of wires.

p-0006In the case of a typical twisted-pair cabling, a first pair of wires <b>11</b> which is frequently coded blue, blue/white is allocated to contacts <b>24</b> and <b>25</b> of a rack <b>5</b>. Likewise, a second pair of wires <b>12</b> which is frequently coded orange, orange/white is allocated to contacts <b>21</b> and <b>22</b> of a rack. A third pair of wires <b>13</b> which is frequently coded green, green/white is allocated to contacts <b>23</b> and <b>26</b> and a fourth pair of wires <b>14</b> which is frequently coded brown, brown/white is allocated to contacts <b>27</b> and <b>28</b> of a rack.

p-0007Due to its allocation to contacts <b>23</b> and <b>26</b> which is located far apart, the third pair of wires <b>13</b> in particular will lead to increased near-end crosstalk at the other pairs of wires that is promoted by parallel surfaces of the wire pairs relative to each other.

p-0008The contacts known from the state of the art are predominantly made of wire. If wires are also used on the corresponding counterpart of the plug-in connector, contact problems frequently arise since frequently only a point contact will materialize. These contact problems are one of the causes of reflections.

p-0009However, attempts at counteracting this effect by means of contact areas has always led to increased near-end crosstalk in the past.

p-0010The invention has chosen as its objective the avoidance of at least one of the disadvantages described above in an inventive manner.

SUMMARY OF THE INVENTION

p-0011As a solution, the invention proposes a contact field for a plug-in connector for twisted-pair cablings. The contact field is equipped with several metallic contacts for a connection with a twisted-pair socket, with each metallic contact having a feed line section for a connection with a circuit board. The metallic contacts are formed from contact sheet metals, with at least two feed line sections being offset relative to other feed line sections.

p-0012In one embodiment of the invention, the contact field is equipped with eight metallic contacts so that a twisted-pair cabling can be provided for common systems of telecommunication, information transmission and computer technology, for example ISDN and Ethernet cabling.

p-0013In yet another embodiment of the invention, the third and sixth feed line sections of the feed line segments are arranged offset relative to adjacent feed line sections.

p-0014In yet another embodiment of the invention, the contacts and their respective feed line sections are executed in one piece.

p-0015In yet another embodiment of the invention, the contact field is an RJ45 contact field.

p-0016In yet another embodiment of the invention, the contact field is suitable to meet the specification under CAT6a.

p-0017In yet another embodiment of the invention, the contact field is equipped with a housing made of insulating material.

p-0018In yet another embodiment of the invention, the contact field is part of a print panel connector.

BRIEF DESCRIPTION OF THE DRAWINGS

p-0019In the following, the invention will be explained in detail with references to the figures. They show:

p-0020<figref idrefs="DRAWINGS">FIG. 1</figref>, the schematic allocation of wire pairs of a twisted-pair cabling to the contacts of a twisted-pair plug board, in particular of an RJ45 plug,

p-0021<figref idrefs="DRAWINGS">FIG. 2</figref>, a contact field of a plug-in connector according to the invention in a first detail,

p-0022<figref idrefs="DRAWINGS">FIG. 3</figref>, a schematic arrangement of a plug-in connector according to the invention in another detail, and

p-0023<figref idrefs="DRAWINGS">FIG. 4A</figref>, illustrates an L-shaped embodiment of contact plates, <figref idrefs="DRAWINGS">FIG. 4B</figref> illustrates a C-shaped embodiment of contact plates, <figref idrefs="DRAWINGS">FIG. 4C</figref> illustrates an L-shaped offset arrangement, <figref idrefs="DRAWINGS">FIG. 4D</figref> illustrates an example of a C-shaped offset arrangement, <figref idrefs="DRAWINGS">FIG. 4E</figref> illustrates an L-shaped embodiment of contact plates, <figref idrefs="DRAWINGS">FIG. 4F</figref> illustrates a C-shaped embodiment of contact plates, <figref idrefs="DRAWINGS">FIG. 4G</figref> illustrates an I-shaped embodiment of contact plates, and FIG., <b>4</b>H illustrates an I-shaped embodiment of contact plates.

REFERENCE SIGN LIST FOR DRAWINGS

p-0024<b>1</b> plug-in connector detail

p-0025<b>2</b> circuit board

p-0026<b>4</b> metallic contacts

p-0027<b>5</b> housing

p-0028<b>6</b> feed line sections

p-0029<b>7</b> circuit board hookup

p-0030<b>8</b> contact area

p-0031<b>11</b> through <b>14</b> wire pairs

p-0032<b>21</b> through <b>28</b> contacts

DETAILED DESCRIPTION OF THE INVENTION

p-0033A detail of an embodiment of a plug-in connector according to the invention is shown in <figref idrefs="DRAWINGS">FIG. 2</figref>.

p-0034In this case, the contact field is equipped with several metallic contacts <b>4</b> for a connection with a twisted-pair socket, with each metallic contact <b>4</b> having a feed line section <b>6</b> for a connection with a circuit board <b>2</b>.

p-0035The metallic contacts <b>4</b> are formed from contact plates, with at least two of the feed line sections <b>6</b> being arranged offset relative to other feed line sections <b>6</b>.

p-0036As can be easily seen in the drawing, the metallic contacts <b>4</b> and the respective feed line sections <b>6</b> may be formed as part of a plate—i.e. as one piece—so that the contact field can construct the metallic contact <b>4</b> with the corresponding counterpart to the plug-in connector on one side and is equipped with the feed line section <b>6</b> to a circuit board for a contact with the corresponding wire on the other side.

p-0037The offset arrangement of feed line sections <b>6</b>—in <figref idrefs="DRAWINGS">FIG. 3</figref>, feed line sections <b>23</b> and <b>26</b> that are arranged offset relative to the other feed line sections <b>21</b>, <b>22</b>, <b>24</b>, <b>25</b>, <b>27</b>, <b>28</b> in relation to their arrangement on a circuit board <b>2</b>—achieves that parallel surfaces of allocated adjacent wire pairs <b>11</b>, <b>12</b>, <b>13</b>, <b>14</b> are reduced according to <figref idrefs="DRAWINGS">FIG. 1</figref>.

p-0038In a typical twisted-pair cabling, the feed line sections <b>23</b> and <b>26</b> correspond, as previously shown in <figref idrefs="DRAWINGS">FIG. 1</figref>, to the third wire pair which tends to strong near-end crosstalk into the other wire pairs.

p-0039By avoiding parallel surfaces of this third wire pair <b>13</b> relative to the other wire pairs <b>11</b>, <b>12</b>, <b>14</b> in the area of the feed line sections <b>6</b> themselves, the near-end crosstalk will be effectively reduced.

p-0040The contact with the circuit board can be realized by means of a circuit board hookup <b>7</b>, e.g. in the form of a soldering connection—see for example FIG. <b>4</b>A—or, for surface mounting as it is known from SMD technology, by providing an appropriately bent surface.

p-0041Here, too, the parallel surface can be reduced further by appropriately placing the circuit board hookup <b>7</b>. This can easily be seen in, for example, <figref idrefs="DRAWINGS">FIG. 4A</figref>.

p-0042In <figref idrefs="DRAWINGS">FIGS. 4A-4H</figref>, various embodiments of contact plates, such as for example, L-shaped contact plates in <figref idrefs="DRAWINGS">FIG. 4A</figref>, <b>4</b>C, and <b>4</b>E, C-shaped contact plates in <figref idrefs="DRAWINGS">FIGS. 4B</figref>, <b>4</b>D, and <b>4</b>F, and I-shaped contact plates in <figref idrefs="DRAWINGS">FIGS. 4G and 4H</figref> according to the invention are shown.

p-0043An L-shaped embodiment of a contact plate <b>4</b> is shown schematically in <figref idrefs="DRAWINGS">FIG. 4A</figref> (the extreme left upper half). The contact area <b>8</b> which serves the contact with a socket is located in the upper region, shown in black. Adjoining it is the feed line section <b>6</b>, followed by a circuit board hookup <b>7</b>.

p-0044A corresponding C-shaped embodiment is represented in <figref idrefs="DRAWINGS">FIG. 4B</figref> (the left upper middle half). The contact area <b>8</b>, drawn in black, which serves a contact with a socket is located in the upper area. Adjoining it is the feed line section <b>6</b>, followed by a circuit board hookup <b>7</b>.

p-0045The offset arrangement of the same embodiment is shown in <figref idrefs="DRAWINGS">FIGS. 4C-4D</figref>, each case below <figref idrefs="DRAWINGS">FIGS. 4A-4B</figref> (the two left upper embodiments). As one can clearly see, the sections <b>6</b> of each of <figref idrefs="DRAWINGS">FIGS. 4A-4B</figref> (upper representation) are offset relative to the representation in <figref idrefs="DRAWINGS">FIGS. 4C-4D</figref> (lower representation). The same also applies to the circuit board hookups <b>7</b> that are likewise arranged offset. In this way, both arrangements may be realized by means of one single type of contact plate <b>4</b>.

p-0046However, the invention is not limited thereto.

p-0047As one sees in <figref idrefs="DRAWINGS">FIGS. 4E-4H</figref> (the right half of Illustration <b>4</b>A-H), varying embodiments of contact plates <b>4</b> may be combined in order to achieve an offset arrangement of the feed line sections <b>6</b>.

p-0048An L-shaped embodiment of a contact plate <b>4</b> is shown in <figref idrefs="DRAWINGS">FIG. 4E</figref> (the center right half) in comparison with an I-shaped embodiment in <figref idrefs="DRAWINGS">FIG. 4G</figref>. Again, the contact areas <b>8</b> are drawn in black.

p-0049In <figref idrefs="DRAWINGS">FIG. 4F</figref> (the extreme right half), a C-shaped embodiment of a contact plate <b>4</b> is represented in comparison with an I-shaped embodiment in <figref idrefs="DRAWINGS">FIG. 4H</figref>. Again, the contact areas <b>8</b> are drawn in black.

p-0050It can be seen without any further ado that the respective feed line sections of <figref idrefs="DRAWINGS">FIGS. 4A</figref>, <b>4</b>B, <b>4</b>E and <b>4</b>F (the upper half) are arranged offset relative to the feed line sections of <figref idrefs="DRAWINGS">FIGS. 4C</figref>, <b>4</b>D, <b>4</b>G and <b>4</b>H (the lower half). The same also applies to the circuit board hookups <b>7</b> which are arranged offset as well.

p-0051It can be seen without any further ado that hybrid forms of L-shaped and C-shaped contact plates <b>6</b> will also lead to the same result.

p-0052It is essential that at least parts of the feed line sections <b>6</b> offset to each other such that they are not overlapping.

p-0053The near-end crosstalk can be reduced by means of these offset arrangements.

p-0054Moreover, the use of contact plates facilitates a stable connection with the corresponding counterpart of the plug-in connector so that—even if this counterpart should be equipped with wires—an improved contact can now be realized since the wire can lie against the contact plate in almost flat fashion, thereby creating an enlarged contact surface.

p-0055The invention hereby makes it possible to effectively solve one or several of the aforementioned problems. In particular, the invention solves the current discrepancy which precludes the use of plates for area contacts in view of increased near-end crosstalk that was noticeable previously.

p-0056In one embodiment of the invention, the contact field is equipped with eight metallic contacts <b>4</b> so that a twisted-pair cabling can be provided for common systems of telecommunication, information transmission and computer technology, for example ISDN and Ethernet cablings. In those cases, the contact field will involve an RJ45 contact field.

p-0057The invention makes it possible to provide plug-in connectors that meet the specifications under CAT6a and higher.

p-0058In yet another embodiment of the invention, the contact field is equipped with a housing <b>5</b> made of insulating material.

p-0059This housing <b>5</b> serves as receptacle for the contacts and can provide, for example, the metallic contacts <b>4</b> as a plug-in array while, on the other hand, it may be quipped with corresponding connecting links for a print mounting on a circuit board <b>2</b>.

p-0060It is particularly preferred that the metallic contact be made as one piece and of a similar type, e.g. L-shaped or C-shaped.

p-0061An L-shaped embodiment is represented in <figref idrefs="DRAWINGS">FIGS. 2 and 3</figref>.

p-0062This, like the C-shaped embodiment, proves to be particularly suitable since to this end, only one single punching tool will be required for all contacts and the offset contacts can be realized by a 180° rotation of the arrangement of the L-shaped plate piece.

p-0063On the one hand, the L-shaped model achieves an offset arrangement on the circuit board <b>2</b> and the overlapping area is minimized as well. Moreover, the L-shape permits a mechanically stable execution of the contacts.

p-0064In a preferred manufacturing process, contact plates <b>4</b> are installed in a housing <b>5</b>. The orientation of the contact plates <b>4</b> is taken into account during the installation, i.e. in the case of an RJ45 connector, the 3^rdand 6^thcontacts are installed at a 180° rotation relative to the other contacts.

p-0065The installation itself may involve a force fitting. It is understood that other measures for securing the contacts in the housing <b>5</b> are usable as well.

p-0066Subsequently, the created contact field is connected as a circuit board plug with a structurally prepared circuit board <b>2</b>. Such a circuit board <b>2</b> may also be equipped with additional contact fields <b>3</b> for a connection with the wire pairs <b>11</b>, <b>12</b>, <b>13</b>, <b>14</b> as well as with additional circuiting, e.g. of balancing networks, fuse elements or the like.

p-0067To this end, the circuit board hookup <b>7</b> may be executed as pin contacts to be inserted in corresponding soldering openings of a circuit board <b>2</b>.

p-0068In an alternative embodiment, the circuit board hookup <b>7</b> may be executed for surface soldering on corresponding soldering pads of a circuit board <b>2</b>.